There is well known a control apparatus for a hybrid vehicle provided with (i) an engine; (ii) a first motor/generator; (iii) a second motor/generator which is operatively connected to an intermediate power transmitting member; (iv) a differential mechanism having three rotary elements to which the engine, first motor/generator and intermediate power transmitting member are respectively connected; (v) a step-variable transmission which constitutes a part of a power transmitting path between the intermediate power transmitting member and drive wheels and which is placed in a selected one of a plurality of speed positions with engagement of a selected one or ones of a plurality of coupling devices; and (vi) an electric power storage device to and from which an electric power is supplied from and to the first motor/generator and the second motor/generator. A hybrid vehicle disclosed in JP-2014-223888A is an example of this type of vehicle. This document discloses a technique of, upon a shifting action of the step-variable transmission, controlling a torque of the first motor/generator and a torque of the second motor/generator, based on a torque of the engine and a torque capacity of the step-variable transmission, such that a rotational acceleration value of the second motor/generator and a rotational acceleration value of the engine coincide with respective target values, wherein each of the target values is compensated in a manner that satisfies a certain limitation applied to the target value. The limitation is determined, for example, depending on a condition required to protect the electric power storage device. The target value is compensated to be within a range between upper and lower limits that are determined depending on a maximum discharging amount and a maximum charging amount of the electric power storage device, when the target value is outside the range between the upper and lower limits.
In JP-2014-223888A, each of the target values is compensated when the target value is outside the range between the upper and lower limits. However, it is difficult to precisely know or grasp a target trajectory that is to be followed by each of the target value during the shifting action of the step-variable transmission, and accordingly difficult to satisfy shifting performance requirements such as shifting shock reduction and shifting responsiveness.